upm/examples/c/mcp2515-txrx.c
Jon Trulson 6a4f06d51b mcp2515 C examples: add default config for Arduino 101
Signed-off-by: Jon Trulson <jtrulson@ics.com>
2017-03-30 17:34:31 -06:00

153 lines
4.9 KiB
C

/*
* Author: Jon Trulson <jtrulson@ics.com>
* Copyright (c) 2016 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <upm_utilities.h>
#include "mcp2515.h"
bool shouldRun = true;
void sig_handler(int signo)
{
if (signo == SIGINT)
shouldRun = false;
}
int main(int argc, char **argv)
{
signal(SIGINT, sig_handler);
// by default we just receive packets
bool do_tx = false;
// if an argument is given, we will transmit packets
if (argc > 1)
do_tx = true;
//! [Interesting]
// NOTE: This example assumes that only two devices are connected
// to the CAN bus, and that both devices are running this example;
// one in TX (transmit) mode, and one in RX (receive) mode.
// If this is not the case, then in rx mode you may see other
// packets from other devices, or not, depending on whether the
// speed is correct for the network. In tx mode, errors may be
// generated on the bus, especially if the CAN bus speed does not
// match the rest of the network.
// You should start the receiver example first. The transmitter
// example will fail after about 5 seconds (timeout) of not being
// able to transmit a message.
// Instantiate a MCP2515 on SPI bus 0 using a hw CS pin (-1).
#if defined(CONFIG_BOARD_ARDUINO_101)
// ARDUINO_101 (Quark core) where you must use SPI
// Instantiate a MCP2515 instance using default SPI bus and pin 10 as CS
mcp2515_context sensor = mcp2515_init(0, 10);
#else
// Instantiate a MCP2515 on SPI bus 0 using a hw CS pin (-1).
mcp2515_context sensor = mcp2515_init(0, -1);
#endif
if (!sensor)
{
printf("mcp2515_init() failed\n");
return 1;
}
// By default, after initialization, the baud rate is set to
// 50Kbps, and the mode is NORMAL, so we don't need to set any of
// that here.
if (!do_tx)
printf("RX mode, waiting for packets...\n");
// our TX payload. If transmitting, the first number will be
// incremented (and rollover) on each transmission.
uint8_t myPayload[8] = {0, 1, 2, 3, 4, 5, 6, 7};
while (shouldRun)
{
if (do_tx)
{
// lets build up a packet and try loading it.
printf("Loading a packet of 8 numbers into a tx buffer...\n");
if (mcp2515_load_tx_buffer(sensor, MCP2515_TX_BUFFER0, 0,
false, false, myPayload, 8))
{
printf("mcp2515_load_tx_buffer() failed\n");
return 1;
}
// now lets try to transmit it
printf("Transmitting packet...\n");
upm_result_t rv = 0;
if ((rv = mcp2515_transmit_buffer(sensor, MCP2515_TX_BUFFER0,
true)))
{
printf("mcp2515_transmit_buffer() failed with code %d\n", rv);
return 1;
}
// increment the first number for each transmission
myPayload[0]++;
printf("Transmit successful\n\n");
upm_delay_ms(500);
}
else
{
// RX mode
// Look for a packet waiting for us in RXB0
if (mcp2515_rx_status_msgs(sensor) == MCP2515_RXMSG_RXB0)
{
printf("Packet received in RXB0, decoding...\n");
// now lets retrieve it
MCP2515_MSG_T msg;
if (mcp2515_get_rx_msg(sensor, MCP2515_RX_BUFFER0, &msg))
{
printf("mcp2515_get_rx_msg() failed\n");
return 1;
}
mcp2515_print_msg(sensor, &msg);
printf("\n");
}
upm_delay_ms(100);
}
}
printf("Exiting...\n");
mcp2515_close(sensor);
//! [Interesting]
return 0;
}